Quarter-inch thick drives will be used to build a new class of ultra-thin and light notebooks

At the behest of equipment manufacturers looking to build a new class of ultra-thin notebooks, Hitachi GST announced today it will begin shipping quarter-inch thick hard drives -- 26 percent slimmer than the current drives in most laptops and netbooks today.

"Netbooks today aren't necessarily thin. They're low cost. What [manufacturers] are trying to do is move up from the standard netbook, to ultra-thin and light notebooks," said Brendan Collins, Hitachi GST's vice president of marketing. "So they're trying to add more value and move consumers up the price ladder from around $300 to more like a $500 to $600 range."

Collins said upcoming ultra-light notebooks for which the new drives are being produced target a market segment between low-end netbooks and high-end, ultra-thin notebooks, such as the Macbook Air. The ultra-light notebooks are expected to roll out in the third quarter of the year.

Hitachi's new Z-series drives are .27-in thick and have a single spinning platter with up to 320GB capacity, the same capacity as the company's .37-inch thick, single-platter predecessors. Collins said Hitachi is not releasing a suggested retail price because it sells to equipment manufactures or resellers, who then determine the pricing.

( (Hitachi's Z-series drives are designed to replace its 9.5mm or .37-in high, single platter drives(

Hitachi said the drive slim down was prompted by laptop manufacturers such as Dell, HP, Lenovo, and Acer, which are all planning to produce thinner, lighter notebooks. The new hard drives, however, will serve multiple markets, including television set-top boxes and portable video players, Collins said.

The Z-series includes three drives: the Travelstar Z7K320, a 7200rpm drive with 16MB cache for use in higher-performance notebooks, ultra portables and netbooks; the Travelstar Z5K320, a 5400rpm drive with 8MB cache with lower power usage, lower cost and quieter acoustics for mobile and ultra-portables; and the CinemaStar Z5K320, a 5400rpm drive with 8MB cache for use in A/V streaming devices such as set-top boxes, portable video players, DVR-enabled TVs and video surveillance systems.

The Z5K320 series drives will ship in volume in July; the Z7320 will begin shipping in August, Collins said. "That 320GB capacity point is the sweet spot in the market today," he said.

Hard drives with a single disk platter represent about 70 percent of the PC drive market today, according to Brendan Collins, vice president of marketing at Hitachi GST. Two-disk drives provide 1TB and 2TB capacities.

"Ideally, you'll be able to use these drives in netbooks, in ultra-thin and light notebooks and in the higher-end notebooks as well. You can use them from top to bottom," Collins said. "That's a big change."

The new slimmer drives are mechanically compatible with their thicker predecessors, meaning their serial ATA connection and side mounting holes are the same so that the drives are interchangeable in laptops, Collins said.

Hitachi said that, considering cost-per-gigabyte and gigabyte-per-cubic-inch, the Z-series drives are more cost-effective and space-efficient than solid-state drives (SSDs), as well as thicker 2.5-inch and 1.8-inch hard drives that also come in 320GB capacities.

SSDs can be 17 times the cost of a hard disk drive and and 1.8-inch drives can be up to seven times more expensive on a cost-per-gigabyte basis when compared to the new Hitachi Z-series drives, the company stated in its marketing material.

According to market research firm Forward Insights, for PC, notebook and netbook manufacturers, SSD prices are around $1.90 per gigabyte today. Hard drives cost about 30 cents per gigabyte.

Lucas Mearian covers storage, disaster recovery and business continuity, financial services infrastructure and health care IT for Computerworld. Follow Lucas on Twitter at @lucasmearian or subscribe to Lucas's RSS feed. His e-mail address is lmearian@computerworld.com.